The invention relates to devices suitable for identifying or authenticating a subject, and to methods making use of such devices.
Face recognition devices are known that include a plurality of cameras in order to cover an acquisition volume as is needed for matching morphologies and for ergonomic comfort, the cameras being arranged so as to cover as large as possible a field with the fields of the cameras overlapping sufficiently. In such devices, the optical axes of the cameras may be parallel and horizontal as in the SmartGate® system. By way of example, those systems make it possible to authenticate a subject by confirming or invalidating the alleged identity of a subject on the basis of one or more images of the subject taken by the cameras and after comparing them with reference data stored in a data storage medium.
Other systems may use cameras having optical axes that coincide in order to maximize the volume in which the subject comes within the field of the various cameras. Such systems enable triangulation to be performed and thus make it possible to perform three-dimensional (3D) reconstruction of the position of a zone of the subject's face by using cameras having fields of view that overlap.
Nevertheless, both of the two above-described types of system can be less than optimal for constituting a multi-biometric system for two-dimensional (2D) face recognition and for iris recognition relying on 3D locating of the eyes by triangulation.
Furthermore, systems having optical axes that coincide have at least one camera with its optical axis pointing upwards. This can lead to the camera being dazzled by sunlight or by lighting situated high up, and can thus lead to a reduction in identification performance.
Furthermore, it can be desirable to minimize the size of devices for identifying or authenticating a subject, in particular when such devices are for use in airport zones.
There thus exists a need for obtaining devices that are useful for identifying or authenticating a subject and that are suitable for being used in satisfactory manner both for performing face recognition of the subject and for determining the 3D position of a zone of the subject's face.
There also exists a need for obtaining devices that are useful for identifying or authenticating a subject and that present performance that is little affected by ambient lighting conditions.
There also exists a need for obtaining devices that are useful for identifying or authenticating a subject and that are of limited size.
There also exists a need for obtaining devices that are useful for identifying or authenticating a subject and that present calculation times and operating costs that are small.